Apparatus for positioning strip



April 15, 1952 T, LORlG 2,593,158

APPARATUS FOR POSITIONING STRIPS Filed Feb. 23, 1950 4 Sheet-Sheet 1 1 4 32 P m TIEZIIZ I N V EN TOR.

' v EDWIN T. LORIG l ATTORNEY April 15, 1952 I E. T. LQRIG APPARATUS FOR POSITIONING STRIPS Filed Feb. 23. 1950 I 4 Sheets$heet 2 e4 e0 72 azJ 80 s 8662 64 INVENTOR. 82 EDWIN T. LORIG ATTORNEY April 15, E T LQRIG APPARATUS FOR POSITIONING STRIPS Filed Feb. 25, 1950 4 Sheets-Sheet 5 INVENTOR. EDWIN T. LORIG ATTORNEY April 15, 1952 E. T. LORIG 2,593,158

APPARATUS FOR POSITIONING STRIPS Filed Feb. 23, 1950 4 Sheets-Sheet 4 ATTORN EY Patented Apr. 15, 1952 APPARATUS FOR POSITIONING STRIP Edwin T. Lorig, Pittsburgh,Pa., assignor to United States Steel Company, a corporation of New Jersey Application February 23, 1950, Serial No. 145,648

Phis invention relates to apparatus for automatically centering and aligning moving objects, especially strip and strip-like materials. In the processing of metal strip, the stri is conveyed over rous in the uncoiled condition, When the strip i's-conveyed over a roll to the processing equipment it is likely that the strip will be fed at a slight angle to the roll. Because of this, the strip will work its way across the face of the roll. In addition, the camber and/oi lateral curvature which is present in the finished strip due to rolling difficulties causes the strip edges and longitudinal center line to approach the roll at an angle, this also causing the strip to move across the face of the roll. In order to keep the strip in the desired path of travel, various expedients have been resorted to. One of the most common is the use of stationary or rotatable side guides against which the edges of the strip bear. used in conjunction with looper pits to force the strip back on the desired center line. The use of abnormally high strip tension has also been tried in an attempt to keep the strip aligned. Another method of operation is to periodically slip or slue the strip back into its approximate proper position on the conveying roll. All of the above methods of centering strip tend to abrade and mutilate the strip edges and in some instances cause the edges of the strip to be stretched beyond the elastic limit of the metal. Diagonal or lateral surface scratches are also formed on finely finished flat products of all kinds, these scratches being detrimental to subsequent operations and together with edge damage result in the scrapping of a large percentage of the material being processed. The problems discussed above also exist in belt con- In some instances side guides have been 17 claims; (01. 271-25) veyors and drive belts used in conjunction with belt pulleys. If the belt is made of rubber or other relatively soft material, it is more easily damaged. In addition to the methods of aligning strip mentioned above, crown rolls have been used to" center materials having a low modulus of elasticity such as textiles, rubber and composition belts.

Two types of apparatus for centering and aligning strip are shown in my copending applications entitled fApparatus for Positioning Strip," Serial No. 97,218, filed June 4, 1949; and "Methodand Alrmaratus for Positioning Strip, Serial No. 138,389, filed January 13, 1950.

It is an object of the present invention to provide apparatus for automatically centering moving objects without damage thereto.

This and other objects will be more apparent .after referring to the following description and attached drawings, in which: p

- Figure 1 is a sectional view of onespecific embodiment of my device;

Figure ,2 is a sectional view taken on the line IL-II of Figure 1;

Figure 3 is .a sectional view taken on the line II I---;;[I of Figure 1;

Figure 4 is a view, similar to Figure 1, showing a slight modification thereof; 1

Figure 5 is a sectional view of another embodiment of my device; t

Figure 6 'isa sectional view taken on the line "VI--VI of Figure 5;

Figure 7 is a sectional view of still another embodiment;

Figure 8 is a sectional view taken on the line VIII-VIII of Figure 7;

Figures 9 to 13, inclusive, show various other embodiments of my device;

Figure 14 is a sectional view taken on the line XIV-XIV of Figure 13; and

Figure 15 is a sectional view of another embodiment of my device.

Referring more particularly to Figures 1, 2, 3, and 4 of the drawings, the reference numerals 2 and 4 indicate a pair of opposed spaced-apart rotatable frusto-conical rolls over which a strip or strip-like material S, such as a conveyor belt, passes. The conical effect in Figures 2 and 4 is exaggerated to show the aligning principle involved in the invention more clearly.- In actual practice this effect can vary from zero to several degrees of angularity on the outer surfaces of the rolls from the center diameter of the roll assembly to the outer edges. In some cases, the conical effect may be reversed to secure troughing. The rolls 2 and 4 are mounted ona shaft 6 which is shown as straight and rotatable, but

which could also be bent and non-rotatable. The

the shaft 6.

shaft 6 is provided with spaced-apart spherical grooves 8 and I0 which extend around its periphery. The rolls 2 and 4 have rim portions I2 and M, respectively, which are connected to inwardly extending web portions 16 and I8. Mounted on each side of the webs l6 and I8 are rubber thrust washers 20 which are held in place againstthe openings 28 in the web portions I6 and I8. The openings 28 are larger than the pins 26 to permit some relative movement between the rolls 2 and 4 and the shaft 6. In some instances a rubber centering member 30 is mounted on the shaft 6. The member 30 extends between the rolls 2 and 4 and its -ends bear against shoulders 32 and 34 on the rim portions I2 and I4, respectively. Grooves 36 are provided in the periphery of the member 30 to provide greater resiliency in the surface thereof. The shaft 6 is mounted in bearings 38 and is provided with a driving extension 39 at one end thereof. In some instances the inner washers 20 and collars 22 may be omitted as shown in Figure 1. In other instances, the centering member 30 may be omitted as shown in Figure 4.

The rolls 2 and 4 are dynamically balanced for rotation about centers 40 and M, respectively, and in their normal position there is an equal space 42 between therims I2 and I4 as shown in Figure 4. When pressure is applied to the surface of the rolls 2 and 4 by means of the'strip S, the rotating rims I2 and I4 tilt and move inwardly toward each other at the point of contact and outwardly at a point diametrically opposite as shown in Figure 1. Rotation of the rolls under pressure applied by strip S will continue in a tilted manner as shown in Figure 1 around centers 40 and 4|, respectively, the axes of rolls 2 and 4 remaining inclined inwardly and downwardly toward the transverse center line of the roll assembly as long as pressure is applied by strip S. As long as the strip S is centered on the roll and the bearing pressure of the strip on the roll is uniform over its full width, no lateral movement of the strip will occur when it is conveyed over the roll. If, however, the strip is offcenter or the strip contact pressure is non-uniform from side to side, the roll lraving the greatest total amount of tension and pressure applied thereto will be bent inwardly toward the shaft 6 a greater amount than the other roll. This will force the strip toward the center of the roll assembly. In other words, as shown in Figure 1, if more of the strip is to the right of the transverse center line of the roll assembly, the roll 2 will be forced downwardly a greater amount than roll 4 so that the strip S will be forced to the left until the strip centers itself. If the tension on the right side of the strip is greater than that on the left, the same result follows. In certain applications there will be only line contact between the roll and the objects passing thereover. In other instances such as shown in Figure 2, the strip S may lead onto the centering roll assembly at point 44 and leave the roll at point 46'. The roll may be either a driven or an idler roll with P2 being greater than F I. Under these conditions the strip will be restored toward the center between points 44- and 48 but there will bea tendency to repel between points 48 and 46. If the direction of rotation is changed PI will be greater than P2 and the restoring and repelling zones will be reversed.

Figures and 6 show another embodiment of my invention in which frusto-conical rolls 50 and 52 are mounted on a shaft 54 which is mounted for rotation in bearings 56. An extension 58 is provided on the shaft 54 if it is desired to drive the rolls. The rolls 50 and 52 have spherical openings 60 and 62 therein for receiving the shaft 54. Each of the rolls 50 and 52 has an outwardly extending opening 64 adjacent the openings 60 and 62 so that a shoulder 66 is provided adjacent 4 the openings 60 and 62. The rolls 50 and 52 are held in place on the shaft by means of a flexible rubber washer 68 bearing against the shoulder 66 and held in position by means of an adjusting nut I0 threaded on the shaft 54. The large end of each of the rolls 50 and 52 is provided with a semi-spherical opening I2 for receiving a spherical aligning member I4 which extends between the rolls 50 and 52 and into the openings I2. The member I4 is provided with a bore I6 of considerably greater diameter than the diameter of shaft 54. When the shaft 54 is driven the rolls 50 and 52 are keyed thereto by means of loose fitting keys I8. For idler rolls the adjacent ends of the rolls 50 and 52 are slotted at to receive driving pins 82 which are threaded into the member 14, The rolls 50 and 52 are dynamicall balanced for inclined rotation about their centers of mass 84 and 86, respectively. The operation of this roll assembly is the same as that shown in Figures 1 to 4 except that the axes of rolls 50 and 52 when deflected under pressure of strip S will always be inclined in synchronism a like amount regardless of pressure distribution because of the aligning ability of spherical member I4.

Figures 7 and 8 show another embodiment of my invention which is quite similar to that shown in Figures 5 and 6. As shown, frusto-conical rolls 88 and 98 are mounted on spherical surfaces 92 and 94, respectively, of a shaft 96. The rolls 88 and are held in place on the shaft 06 by means of a rubber thrust member 98 which is held against a shoulder I00 on each of the rolls 88 and 90 by means of a collar I02 and a nut I04 threaded on the shaft 06. If desired, lock washers I05 may be provided for the nuts I04. A spherical member I06 similar to member I4 is provided between the rolls 88 and 90. The rolls 88 and 90 may be driven in synchronism by means of a pin I08 fastened to the end of roll 88 and extending between the rolls 88 and 00 into an elongated slot I I0 in theroll 90. The operation of this roll assembly is the same as the roll assembly of Figures 5 and 6.-

Figure 9 shows another embodiment of my invention in which frusto-conical rolls II2 and H4 are mounted on spherical bearings II6 carried on a shaft II8. A centering member I20 rigidly attached to shaft I I8 extends betweenand holds rolls II2 and H4 in place in cooperation with rubber washers I22 which bear against shoulders I24 on the rolls H2 and H4. Driving pins I26 are threaded into each end of the con-.- tering member I20 and extend therefrom into elongated openings I 28 in the rolls II2 and H4. The rolls II2 and H4 are held in place and prevented from moving outwardly on the shaft II8 by means of a collar I30 against which bears a rubber washer I32 which is held in place by means of a collar I34 and a nut I36 threaded on the shaft II8. If desired, lock washers I3! may be provided for the nuts I36. The rolls II2 and H4 are dynamically balanced and the operation of the roll assembly is the same as that of Figures 5 and 8.

Figure 10 shows a further embodiment which is particularly adapted for relatively low speed installations. In this embodiment a pair'of spaced-apart frusto-conical rolls I38 is mounted on a shaft I40 which may be rotatable or nonrotatable. When shaft I40 is rotatable the smaller or outer end of each of the rolls I38 is mounted on a bearing I42 and is provided with an opening I44 in which is received a collar I46. Pins 5 I48 extend from the collars I'AB'into iopenin I50 in the rolls I38. The collar I146: is held against the-bottom of the opening I414 byxmeans of a nut I52 threaded on"t'he shaftilfll'. If desired, loek washers I53 may be provided for the nuts I52. The large end of each of the rolls I38 thus'automatical'ly centering the belt at all-times tering member I58. While the rolls I88 are not dynamically balanced,'the operation thereof is essentially the same as that of the rolls shown in Figures 1 and 2. a

Figure 11 shows an embodiment of my invention quite similar to that of Figure'ld. In'this embodiment a pair of rolls IE8 is providedeach of which consists ofa rim portion I52 fastened to a hub portion I64'which is keyed to a shaft I66. The operation of this device is the same asthe d ice of Fig e l x ptt t hes1 shb resilience in the materials of which the roll assembly is constructed is utilized to secure deflection and resultant progressive tilting 'an 1; inward movement of the rotatin rims of rolls I68 at the large ends of the rolls on the strip approach side when the assembly is under strip ressure. p a

Figure 12 shows an embodiment of my invention which is particularly adapted for use as a pulley in a belt drive. In this embodiment a pair of frusto-conical rolls I18 is provided with an inwardly extending web portion I12. The web portions are held in spaced-apart relationship by means of a hub I14 anda pair of rubber or other resilient washers I16 on each side of each web I12. A plurality of bolts I18 extends through aligned openings in the webs I12, hub I14 and washers I16 to hold theassembly together. It will be noted that the rims of the rolls I10 are spaced apart in the same manner as the rims of the rolls in the previous embodiments so that the rims are free to move toward each other about pivot points I80. The roll assembly is keyed to a driving shaft I82. In case of high speeds the rolls I10 should be dynamically balanced about points I88. When used as a pulley, a metal belt passes around approximately half of the periphcry of the rims causing them to move toward each other over the area of contact. This causes the belt to center itself.

Figures 13 and 14 show another embodiment of my invention which is quite similar to that shown in Figure 12. In this embodiment a pair of frusto-conical rolls I84 each has a rim portion I86 supported by a plurality of spokes I88 extending inwardly and fastened to a'hub I98 by means of a plurality of bolts I92. It will be noted that the spokes I88 are bowed with the concave surfaces of the ,spokes of one roll facing the concave surfaces of the spokes of the other roll. The spokes I88 may be replacerlby a thin continuous web portion. The hub I90 is keyed to a driving shaft I94. When used as a pulley, a belt B is wrapped around ap roximately half the periphery of the rim from points I96 to I98 and when pressure is applied thereto the spokes I88 between points I96 and I98 will be flexed slightly toward the vertical center line of the :pulley and the spokes between points I98 and I98 will be flexed away from the center line,

during rotation; a j

A very slight modification of the pulley shown in Figures 13 and M is shown in Figure 15,. In this embodiment the rolls 2811 are made in one piece from a thin metal sheet with the web portion being corrugated at 8.82, as shown. Otherwise the construction and operation is the same as that of the pulley shown in Figures 13 and 14.

In the figures described above, pairs of opposed frus-to-conical rolls, the large diameter at the center of the roll assembly, are indicated to be preferable. In some cases, however, cylindrical or frusto-conical rolls having their smalldiameters adjacent one another can be used for specific applications to secure automatic cem tering of objects to be conveyed.

While several embodiments of my invention have been shown and described, it will be appar ent that other adaptations and modifications may be made without departing from the scope of the following claims. I

I clai A Apparatus for positioning a moving object comprising a'pair of coaxially opposed and spaced rotatable rims over which the object passes in a direction transverse to the axes .of the rims, spaced coaxial shaft sections, a shaft extension for at least one of said shaft sections extending outwardly beyond said' rims and adapted to be supported in bearing means, means for supporting said rims on said shaft sections for limited and progressive deflection of the adjacent peripheral ends of said rims adjacent the initial point of contact with the moving object in a direction transverse to the axes of the shaft sections, r silient means forming part of said rim supporting means for limiting deflection of said peripheral ends imposed thereon by the object, and means for positively causing one of said rims to rotate in the same direction and at the same angular velocity as the other rim.

2. Apparatus for positioning a moving object according to claim 1 in which the rims are frustoconical with the large diameter ends thereof being adjacent each other.

3. Apparatus for positioning a moving object comprising a pair of coaxially opposed and spaced g rotatable rims over which the object passes in a direction transverse to the axes of the rims, a

straight shaft, an extension for said shaft extending outwardly beyond said rims. on at least one side thereof and adapted to be supported in bearing means, means for supporting said rims on said shaft for limited and progressive deflec tion of the adjacent peripheral ends of said rims adjacent the initial point of contact with the moving object in a direction transverse to the axes of the shaft, resilient means forming part of said rim supporting means for limiting deflection of said peripheral ends imposed thereon by the object, and means for positively causing one of said rims to rotate in the same direction and at the same angular velocity as the other rim.

4. Apparatus for positioning a moving object according to claim 3 in which the rims are frustoconical with the large diameter ends thereof being adjacent each other.

5. Apparatus for automatically positioning a moving object comprising a pair of axially aligned bearings, a shaft mounted in said bearings, and rotatable means mounted on said shaft between said bearings, said rotatable means including a pair of spaced apart outer object supporting portions, means for positively causing one of the moving object comprising a straight shaft, a

rotatable object supporting member mountedon said shaft, and a shaft extension for said shaft extending outwardly beyond said object supporting member andadapted to be supported in bearing means; said rotatable A member including a pair of spaced apart outer. object supporting portions, means for positively causing one of the spaced apart object supporting portions to rotate in the same direction and at the same angular 7 Velocity as the other object supporting portion,

- and means for supporting each of said object supporting portions for limited and progressive deflection thereof adjacent the initial point of contact with the moving object in a direction transverse to'the axis of said shaft.

SJApparatus for automatically positioning a moving object according to claim '7 in which the object supporting portions are frusto-conical with the large diameter ends thereof being adjacent each other.

9. Apparatus for automatically positioning a moving object according to claim 8 in which the cally balancedlr'olls. I

10; Apparatus for automatically positioning a moving object according to claim 9 in which each of the rolls has a hole therethrough at its center of rotation with said shaft passing therethrough. 11. Apparatus for automatically positioning a moving object according to claim 10 in which each of said rolls has an opening in its large end with a shoulder at the bottom thereof, and an elastic aligning member extending between said rolls into said openings, said aligning member bearing on the walls and shoulders of said openings.

rotatable membergcomprises a pair of dynami- 12. Apparatus for automatically positioning a moving object according to claim 10 in which the parts of said hole in contact with said shaft have a spherical convex surface, each of said rolls having a spherical opening in its large end, and a spherical aligning member extending between said rolls into said openings, said aligning member having an opening therein for passage of said shaft, said last named opening being of considerable greater diameter than said shaft.

13. Apparatus for automatically positioning a moving object according to claim. '7 in which the rotatable member comprises a pair of aligned spaced apart rolls, each of said rolls having a rim and a web portion spaced from the adjacent ends of the rolls.

14. Apparatus for automatically positioning a moving object according to claim 13 in which the rims are frusto-conical with the large diameter ends thereof being adjacent each other.

15. Apparatus for automatically positioning a moving object according to claim 14 in which a hub portion connects the inner ends of said web portions. 1

16. Apparatus for automatically positioning a moving object according to claim 13 in which the web portion comprises a plurality of bowed spokes with the concave surfaces of the spokes of one roll facing the concave surfaces of the spokes of the other roll.

17. Apparatus for automatically positioning a moving object according to claim 16 in which the rims are frusto-com'cal with the large diameterends thereof being adjacent each other.

EDWIN T. LORIG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 909,833 vrooman Jan. 12, 1909 1,189,611 Morse July 4, 1916 1,741,852 LeRud Dec. 31, 1929 1,846,665 Adams Feb. 23, 1932 1,879,232 Henry Sept. 27, 1932 1,927,849 Roberts Sept. 26, 1933 2,127,643 Glossman Aug. 23, 1938 2,198,656 Cohn et a1. Apr. 30, 1940 JM as 

